1. Field of the Invention
The present invention pertains to fiber optics or photonics modules. More particularly, this invention relates to a micro-photonics module having a partition wall to provide isolation among various components of the micro-photonics module.
2. Description of the Related Art
Optical communications systems are widely used for carrying very large amount of information with low distortion and at low cost over great distances. For this reason, considerable development has been made on components of optical communication systems, such as photonics packages or modules. Photonics generally refer to devices that share both electronic and optical attributes. These devices can be laser devices, which generate coherent light in response to an electronic signal, and photo detectors, which generate an electronic signal in response to light.
A bidirectional photonics module typically includes a transmitter formed by at least one laser and a receiver formed by at least one photo detector. The laser is typically an edge emitting semiconductor laser and the photo detector is typically a surface detecting photo detector. Since an edge emitting laser has a relatively wide radiation angle, a lens is inserted between the laser and an optical fiber to obtain high optical coupling efficiency. In addition, a lens is typically inserted between the optical fiber and a photo detector. The inserted lens improves the optical coupling efficiency between the optical fiber and the photo detector. Because the photonics module is a bidirectional module, an optical filter is used to reflect the light beam emitted from the optical fiber to the photo detector and to allow the light beam from the laser to reach the optical fiber.
In making such a bidirectional photonics module, all of the optical components must be in precise predetermined alignment with one another to form the transmitter and receiver. To achieve this, fixtures and/or mounts are typically needed to hold the components in place and in alignment with one another.
Disadvantages are, however, associated with such photonics modules or packages. One disadvantage is that such prior art photonics modules are typically relatively costly to fabricate because they typically require relatively high precision. Another disadvantage is that it is typically time consuming to assemble the photonics modules using the fixtures, thus causing low throughput. In addition, time may also be needed for alignment and adjustment during assembling the photonics modules. This typically hinders mass-production of the photonics modules by persons having a moderate level of skill while maintaining the required alignment criteria. These factors typically limit the cost reduction of the photonics modules. Moreover, these photonics modules typically have relatively large size because of the fixtures.
One prior solution is to mount all or most components of a photonics module on a single mounting member or substrate. This, however, creates optical interferences between the transmitter and receiver of the photonics module. For example, some of the light from the laser reflected off the corresponding spherical lens can be picked up by the receiving photo detector, thus causing optical interference. Moreover, because a photonics module also includes electrical components as well as optical components, metal leads are required on the mounting member if the electrical components are to be mounted with the optical components on the same mounting member. When this occurs, the metal leads may function like antenna to generate electrical interference that affect the performance of the optical components (e.g., the laser or photo detector).